Buy the Bowflex SelectTech 552 if you want the most natural round-dumbbell feel and the finest low-end steps; buy the PowerBlock Elite EXP if footprint and durability come first and you want a path to 90 lb without a second purchase. Both replace a rack of fifteen in the space of one pair — this comparison is about which set of compromises fits your room and your training.
The core difference is the shape and the mechanism. The Bowflex is a dial dumbbell: you spin a dial at each end and the handle picks up 5 to 52.5 lb in 2.5 lb steps at the low end. The PowerBlock is a block-in-block cage: you move a selector pin, and the whole thing is shorter than the Bowflex at every weight because it stacks nested U-shaped weights rather than round plates. That single design choice — round plates versus a nested block — drives almost every trade-off below, from how it grips to how it stores to what can break.
Neither is a wrong answer. They're the top two picks in our adjustable dumbbells roundup for good reason. The right call depends on which constraint bites hardest in your space, so the verdict below is split by use case rather than a single winner.
The verdict, by use case
Tightest footprint → PowerBlock
This is the PowerBlock's home win. The block shape is shorter than the Bowflex at every weight, which matters on a narrow bench where a long dial handle can catch your thighs or the floor. If your storage shelf or workout zone is genuinely cramped, the PowerBlock is the space-efficient pick — it was built around the footprint problem.
Most natural feel and fine steps → Bowflex
The Bowflex feels like a normal dumbbell in the hand, and the dial gives clean 2.5 lb jumps at the low end that are genuinely useful for small-muscle and accessory work. The PowerBlock's cage shape is polarizing — some lifters never warm to gripping inside the block, and its fine micro-jumps need separate adder weights. For feel and progression, the Bowflex wins.
Durability and room to grow → PowerBlock
The part that usually fails on a dial dumbbell is the plastic tray, and the PowerBlock mostly doesn't have one — it's an all-metal core with far less to crack. It also expands to 70 or 90 lb with kits, so it grows with you instead of being replaced. If you're rough on gear or expect to get strong, the block is the more future-proof buy.
Everyone else → Bowflex
If neither footprint nor a 52.5 lb ceiling is a hard limit for you, the Bowflex is the easier daily driver: familiar shape, fast dial, fine steps. That's why it's our overall top adjustable pick. Whichever you choose, don't drop them and give the pair a proper home off the floor.
